vSAN cluster usable disk space calculation

[esxi1979]

Hi All

I have 3 servers, each server has 1 ssd & 3 hhd disk 1 TB each. How can i calculate usage size of cluster ? i was told by vmware 80% of (3*3 = 9 ) 9 TB and substract overhead , and overdead size is  difficult to estimate

Any suggestions Please ?

Thanks

[esxi1979]

i found answer

Only magnetic disks (HD) will be used for capacity, and that is the total capacity you will have. Depending on the "failures to tolerate" you will select per VM there will be an x number of copies of your data. So if you add the above up you will have the "raw" capacity, depending on the chosen number of copies your net results will vary.

So my calculation will be 

FT=1

9 TB raw

4.5 TB usable

80% should be target  usage to avoid data cruching

3.6 TB is the final #

thanks @depping

[larstr]

esxi1979,

Also note that if you go to Cluster / Monitor / vSan / Capacity you will find a capacity calculator for your environment:

It will make an estimate for you depending on the storage policy you choose.

Lars